LAB: LATENT HEAT FUSION OF REGULAR ICE AND HOT ICE (SODIUM ACETATE)
Chinaza Nwaneri and Camille Horne. The purpose of this lab was to find the latent heat of three substances, regular ice,hot ice and milk chocolate see which had a larger latent heat. Calorimetry was used to measure the temperature change associated with each phase changes. Ice formed from water gave off 82.416 cal/g while -446.1064 cal/g was given off by the hot ice. In conclusion, both phase changes were exothermic, but the crystallization of hot ice was more exothermic. This supported the hypothesis that the latent heat of hot ice would be larger. Future research could explore the latent heat associated with other phase changes, such as the solidification of chocolate.

Key Terms: Latent Heat, Specific Heat, Calorimetry, Endothermic, Extothermic , Temperature, Heat.

Hypothesis: What was hypothesized in this experiment was that the hot ice would have a higher latent heat.It is used in heat packs and appears to release more heat than water when it crystallizes


Procedure for Creating Hot Ice:

- Get a pan and dissolve the sodium acetate trihydrate crystals in hot, almost boiling water.
- Heat the mixture until it's almost boiling.
- Stir the mixture constantly till there is little extra undissolved powder at the bottom.
- When the solution has dissolved, pour the solution into a glass of any size and cool the glass of the solution in the refrigerator for an hour or 30 minutes
- Pour your solution into a tray or container and touch the solution with a bit of the solid sodium acetate on a toothpick. The solution should turn into a solid as soon as it is touched.

Procedure for Capturing Latent Heat of Ice and Hot ice in the Calorimeter:

-Connect the lab prob and temperature prob to a laptop
- melt the solid chocolates and place them into tubes.
- Mass the calorimeter cup and mass the melted milk and dark chocolate in the tubes
- fill the empty cup with about half a cup of ice and mass it
- take the starting temp of the ice cubes
- Put the chocolate that is made into a test tube and place it in the ice as it begins to crystallize
- place the calorimeter top over the cup and solution and place the temperature prob inside
- For both chocolates, fill ice cubes in the cup around the chocolate until it reaches 5 -10 degrees below the orginal temp, then repeat the calorimeter process like the for dark chocolate.
- Collect the data on the lab pro, once the temperature reaches equilibrium take out the cup and mass it.
- collect the final temperature of the chocolate as well as the volume, and record Data.